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Articles 2821 - 2850 of 34534

Full-Text Articles in Physical Sciences and Mathematics

Method Development For Analysis Of Dietary Supplements Using Flame Atomic Absorption Spectroscopy, Elijah Hongsermeier-Baxter Apr 2022

Method Development For Analysis Of Dietary Supplements Using Flame Atomic Absorption Spectroscopy, Elijah Hongsermeier-Baxter

2022 Student Academic Showcase

Dietary supplements are typically ingested by customers who already have a well-balanced diet and an awareness of a personal, specific deficiency or fitness goal serving as their reason for doing so. Accordingly, the accuracy of the composition of a supplement on its label is paramount in determining if said tablets are worthwhile for customer use. A method was developed to determine the accuracy of the nutrition facts labels on two different brands of iron and zinc supplements. Samples were prepared via dissolution in nitric acid followed by filtration, dilution and analysis via flame atomic absorption spectroscopy. A standard curve method …


Relative Energy Comparison For Various Water Clusters Using Mp2, Df-Mp2, And Ccsd(T):Mp2 Methods, Qihang Wang Apr 2022

Relative Energy Comparison For Various Water Clusters Using Mp2, Df-Mp2, And Ccsd(T):Mp2 Methods, Qihang Wang

Honors Theses

The study of water clusters is an important area of research in many disciplines, such as biology, physical chemistry, and environmental studies. However, due to the difficulty in studying larger water clusters, such as clathrate hydrates, it is beneficial to obtain accurate descriptions of smaller water clusters to use as models for larger systems via computational methods. By starting with small water clusters, such as (H2O)6, and moving into larger systems it is possible to build up data on various water structures that can determine the energetics of the various geometries within a certain number of water molecules. …


Synthesis Of Molecularly Imprinted Polymer For The Detection Of Perfluorooctanoic Acid, Yuqi Wang, Hannah Rhodes Apr 2022

Synthesis Of Molecularly Imprinted Polymer For The Detection Of Perfluorooctanoic Acid, Yuqi Wang, Hannah Rhodes

Liberty University Research Week

Undergraduate

Basic


Inhibiting Nitroso Related Methylation Of Guanine Using Dietary Supplements And Flavonoids, Hannah Klose, Madeline Mccoy, Mary Hall Apr 2022

Inhibiting Nitroso Related Methylation Of Guanine Using Dietary Supplements And Flavonoids, Hannah Klose, Madeline Mccoy, Mary Hall

Liberty University Research Week

Undergraduate

Basic


High-Performance Liquid Chromatography Analysis Of Common Adulterants, Madison Landreth, Elijah Deyoung, Jedidiah Black, Lynza Osorio Apr 2022

High-Performance Liquid Chromatography Analysis Of Common Adulterants, Madison Landreth, Elijah Deyoung, Jedidiah Black, Lynza Osorio

Liberty University Research Week

Undergraduate

Basic


Detection Of 5-Fluoro-2-Oxindole And Products By Hplc After Reaction With Human Liver Enzymes, Kalie Nuss, Emma Mohler Apr 2022

Detection Of 5-Fluoro-2-Oxindole And Products By Hplc After Reaction With Human Liver Enzymes, Kalie Nuss, Emma Mohler

Liberty University Research Week

Undergraduate

Basic


The Effect Of Coca-Cola™ On Fresh And Latent Blood Stains, Brittany Johnson, Bethany Smith, Katie Steigerwald, Rachel Eberle Apr 2022

The Effect Of Coca-Cola™ On Fresh And Latent Blood Stains, Brittany Johnson, Bethany Smith, Katie Steigerwald, Rachel Eberle

Liberty University Research Week

Graduate

Basic


Synthesis And Characterization Of 5,6-Fused Ring Pyridazines, William Hobbs, Joshua Bird, Stephen Carter Apr 2022

Synthesis And Characterization Of 5,6-Fused Ring Pyridazines, William Hobbs, Joshua Bird, Stephen Carter

Liberty University Research Week

Undergraduate

Basic


Utilization Of Solid-State Catalysis For Screening Of Peroxidase Library, Zachariah Hutcheon, Alexa Deckert Apr 2022

Utilization Of Solid-State Catalysis For Screening Of Peroxidase Library, Zachariah Hutcheon, Alexa Deckert

Liberty University Research Week

Undergraduate

Basic


Synthesis Of Re(Co)3[1,2-C5h3(Coc4h3s)2], Chloe Vernon, Ryan Renfro, Wilmar Janusz Apr 2022

Synthesis Of Re(Co)3[1,2-C5h3(Coc4h3s)2], Chloe Vernon, Ryan Renfro, Wilmar Janusz

Liberty University Research Week

Undergraduate

Basic


Limits Of Detection Of Mycotoxins By Laminar Flow Strips: A Review, Xinyi Zhao, Hugh Byrne, Christine M. O’Connor, James Curtin, Furong Tian Apr 2022

Limits Of Detection Of Mycotoxins By Laminar Flow Strips: A Review, Xinyi Zhao, Hugh Byrne, Christine M. O’Connor, James Curtin, Furong Tian

Articles

Mycotoxins are secondary metabolic products of fungi. They are poisonous, carcinogenic, and mutagenic in nature and pose a serious health threat to both humans and animals, causing severe illnesses and even death. Rapid, simple and low-cost methods of detection of mycotoxins are of immense importance and in great demand in the food and beverage industry, as well as in agriculture and environmental monitoring, and, for this purpose, lateral flow immunochromatographic strips (ICSTs) have been widely used in food safety and environmental monitoring. The literature to date describing the development of ICSTs for the detection of different types of mycotoxins using …


Peptidomics Analysis Reveals Changes In Small Urinary Peptides In Patients With Interstitial Cystitis/Bladder Pain Syndrome, Md Shadman Ridwan Abid, Haowen Qiu, Bridget A. Tripp, Aline De Lima Leite, Heidi Roth, Jiri Adamec, Robert Powers, James W. Checco Apr 2022

Peptidomics Analysis Reveals Changes In Small Urinary Peptides In Patients With Interstitial Cystitis/Bladder Pain Syndrome, Md Shadman Ridwan Abid, Haowen Qiu, Bridget A. Tripp, Aline De Lima Leite, Heidi Roth, Jiri Adamec, Robert Powers, James W. Checco

UNL Student Research Days Posters, Graduate

Interstitial cystitis or bladder pain syndrome (IC/BPS) is a chronic and debilitating pain disorder of the bladder and urinary tract with poorly understood etiology. Symptomatic criteria to aid in the diagnosis of IC/BPS includes bladder pain, an increase in urinary urgency or Hunner’s ulcers on the bladder wall.

Our study revealed differences in the profiles of small urinary peptides for IC/BPS patients compared to age-matched controls which is consistent with increased protease activity in IC/BPS. Our study also enabled the direct measurement of APF peptide abundance in IC/BPS and control urine. Our results indicate that the full-length APF peptide was …


Asymmetric Synthesis Of 𝜸-Borylated Amines Via Rhodium-Catalyzed Hydroboration Of Allylamine Derivatives, Rukshani Wickrama Arachchi, Shekhar Kc, Arun Suneja, James Takacs Apr 2022

Asymmetric Synthesis Of 𝜸-Borylated Amines Via Rhodium-Catalyzed Hydroboration Of Allylamine Derivatives, Rukshani Wickrama Arachchi, Shekhar Kc, Arun Suneja, James Takacs

UNL Student Research Days Posters, Graduate

The Takacs group has explored different dimensions of Catalytic Asymmetric Hydroboration (CAHB) reaction mainly focusing on variety of amide, oxime ether and phosphonate directing groups. Inspired by the results obtained with BINOL- and TADDOL- derived chiral catalysts along with pinacolborane, we explored the potential of acyclic N-acyl allylamines as substrates for direct-hydroboration to prepare chiral amine derivatives bearing g-boronic ester functionality, yields up to 90% with 98:2 enantioselectivity. The major enantiomer obtained is independent of starting alkene geometry, revealing that rhodium-catalyzed cis/trans-alkene isomerization occurs prior to hydroboration. In this poster, we will discuss the generation of active catalysts …


Theranostic Copolymers Neutralize Reactive Oxygen Species And Lipid Peroxidation Products For The Combined Treatment Of Traumatic Brain Injury, Aaron Priester, Richard Waters, Ashleigh Abbott, Krista Hilmas, Klaus Woelk, Hunter A. Miller, Aria W. Tarudji, Connor C. Gee, Brandon Mcdonald, Forrest M. Kievit, Anthony J. Convertine Apr 2022

Theranostic Copolymers Neutralize Reactive Oxygen Species And Lipid Peroxidation Products For The Combined Treatment Of Traumatic Brain Injury, Aaron Priester, Richard Waters, Ashleigh Abbott, Krista Hilmas, Klaus Woelk, Hunter A. Miller, Aria W. Tarudji, Connor C. Gee, Brandon Mcdonald, Forrest M. Kievit, Anthony J. Convertine

Chemistry Faculty Research & Creative Works

Traumatic brain injury (TBI) results in the generation of reactive oxygen species (ROS) and lipid peroxidation product (LPOx), including acrolein and 4-hydroxynonenal (4HNE). The presence of these biochemical derangements results in neurodegeneration during the secondary phase of the injury. The ability to rapidly neutralize multiple species could significantly improve outcomes for TBI patients. However, the difficulty in creating therapies that target multiple biochemical derangements simultaneously has greatly limited therapeutic efficacy. Therefore, our goal was to design a material that could rapidly bind and neutralize both ROS and LPOx following TBI. To do this, a series of thiol-functionalized biocompatible copolymers based …


Synthesis Of A Novel Carbon Monoxide-Releasing Gallium Flavonol Complex, Joel Ashton Apr 2022

Synthesis Of A Novel Carbon Monoxide-Releasing Gallium Flavonol Complex, Joel Ashton

Student Research Symposium

Carbon monoxide (CO) has unique therapeutic properties including anti-cancer effects. Flavonols such as 3-hydroxyflavone can release CO upon exposure to visible light. Gallium(III) also has anti-cancer properties and can replace Fe(III) in biological processes. This research was focused on synthesizing a complex of gallium(III) and 3-hydroxyflavone which can hopefully combine the anti-cancer properties of both gallium and CO. Initial attempts to synthesize the complex mimicked those of transition metal flavonol complexes using a base to deprotonate the flavonol and stirring with gallium salt. The most successful synthesis developed involved dissolving 3-hydroxyflavone and gallium nitrate in ethanol and DMSO, adjusting the …


Investigating Position 312 In Prmt1 For Future Fluorescent Labeling Studies, Sarah Nielson Apr 2022

Investigating Position 312 In Prmt1 For Future Fluorescent Labeling Studies, Sarah Nielson

Student Research Symposium

Protein arginine methyltransferase 1 (PRMT1) is an enzyme that post-translationally methylates other proteins in the cell. These methylation events play critical roles in maintaining cellular health. Labeling PRMT1 site-specifically will enable further research in PRMT1 oligomeric state in vivo and can be applied in future fluorescent studies. The intention of this research was to identify a position to label PRMT1 that does not affect oligomerization or activity. Position 312 was chosen as the site for specific tagging as it will have less interference in oligomerization, minimizes free rotation of fluorescent tags, and is surface-exposed. To confirm that position 312 was …


Can Superoxide-Responsive Co Delivery Molecules Be Developed?, Taylor Dittmar Apr 2022

Can Superoxide-Responsive Co Delivery Molecules Be Developed?, Taylor Dittmar

Student Research Symposium

Although known for its toxicity, carbon monoxide (CO) has now been identified as producing beneficial health effects when present at low concentrations. CO is generated in the human body during the breakdown of heme. It is known for its anti-cancer, cardioprotective, and anti-inflammatory effects. To enhance these therapeutic effects, CO delivery molecules have been developed. Fluorescent flavonol-based CO delivery molecules are gaining broad interest due to their triggerable, trackable, and targetable properties. Flavonols can also be used as dual functioning molecules, with additional capabilities such as the detection of reactive oxygen species (ROS) being possible to incorporate in addition to …


The Connections Between Musculoskeletal Injury And Global Reaction, Keaton Reel Apr 2022

The Connections Between Musculoskeletal Injury And Global Reaction, Keaton Reel

Student Research Symposium

The peripheral effects of severe musculoskeletal injury are a well-studied phenomenon, but less well studied are the neural deficits. Past research has demonstrated that such severe injuries, specifically torn and reconstructed anterior cruciate ligament (ACL), may increase cognitive burden due to lack of afferent feedback from damaged nerves. This has previously shown to lead to delayed voluntary reactions in the lower extremities, but global neural changes are currently unknown. The goal of the conducted research was to determine whether neuromuscular deficits due to ACL injury and reconstruction in one limb influences motor behavior on a global level. Simple reaction time, …


Correlation And Comparison Of Some Trace Elements And Their Related Proteins In Type 2 Diabetes Mellitus In Kalars City/ Kurdistan-Iraq., Hero Helal Muhammed Saed, Zeyan Abdullah Ali Apr 2022

Correlation And Comparison Of Some Trace Elements And Their Related Proteins In Type 2 Diabetes Mellitus In Kalars City/ Kurdistan-Iraq., Hero Helal Muhammed Saed, Zeyan Abdullah Ali

Al-Qadisiyah Journal of Pure Science

The serum levels of trace elements alterations have been linked with Type 2 Diabetes mellitus (T2DM) and its complication. The Objectives of this study is to detect the correlation relationbetween serum Chromium (Cr), Magnesium (Mg), Zinc (Zn), Copper (Cu), and Iron (Fe) with Fasting Blood Sugar (FBS) in patients with type two diabetes mellitus, also to study the comparison of Ferroxidase, Transferrin, and Total iron binding capacity in patients with type two diabetes mellitus with control groups. A total of forty subjects were included in this study, they were divided in two groups (control and diabetic patients). Fasting blood samples …


Physical And Chemical Changes In Water Resulting From Contamination With Heavy Metals, Mohammed Khalif Challab Apr 2022

Physical And Chemical Changes In Water Resulting From Contamination With Heavy Metals, Mohammed Khalif Challab

Al-Qadisiyah Journal of Pure Science

Nanoparticle in each model can be damage to water quality. This study is about nanometal in water that damaged to its quality. Metal divided to layers that electrical shock can lead to dividing of them. In different model in about temperature, Energy and different layer, quality of water be measured. Temperature has reverse relation with water quality. The best temperature to electrical shock in (-20) ̊C. electrical shock has direct effect on quality of water. In total investigation on all layers, electrical shock damaged to all layers and bridging phenomena be occurred in particle that can removed from water. With …


Castor (Ricinuscommunis) And Sesame (Sesamumindicum) Biodiesel Optimization By Alkaline Na+/K+ Catalytic Conversion., Aliru Olajide Mustapha, Kamarudeen Seun Akanji, Adebola Christianah Akala, Ebenezer Sola Daramola, Mercy Mobolaji Ajala, Fatimah Yetunde Ajao, Salihu Folorunsho Adisa, Mubarak Bolakale Abdullahi Apr 2022

Castor (Ricinuscommunis) And Sesame (Sesamumindicum) Biodiesel Optimization By Alkaline Na+/K+ Catalytic Conversion., Aliru Olajide Mustapha, Kamarudeen Seun Akanji, Adebola Christianah Akala, Ebenezer Sola Daramola, Mercy Mobolaji Ajala, Fatimah Yetunde Ajao, Salihu Folorunsho Adisa, Mubarak Bolakale Abdullahi

Al-Qadisiyah Journal of Pure Science

For the optimization of refined castor biodiesel (RCB) and refined sesame biodiesel (RSB), the impacts of specified conditions such as catalyst types (NaOH and KOH), catalyst concentration (0.3–1.5 wt. %), speed (500–750 rpm), and time (20–60 min) were investigated. The physicochemical properties of the RCB and RSB were measured using the American Standard for Testing Materials (ASTM) approved protocols for acid, peroxide, iodine, and saponification; density, kinematic viscosity, and refractive index value. Box–Behnken Design's Response Surface Methodology(RSM) was also used for optimization. The results for four optimization methods were catalyst concentration (0.300–0.435 wt. %), speed (500.000–643.242 rpm), and time (20.000–31.386 …


The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity, Harsh Chheda, Rushi Patel, Maria Ballester, Victor Castro Apr 2022

The Effect Of Fluorinated Substitution Of Meso Phenyl Porphyrins On Porphyrin Basicity, Harsh Chheda, Rushi Patel, Maria Ballester, Victor Castro

Chemistry and Physics Faculty Proceedings, Presentations, Speeches, Lectures

The purpose of this study was to determine the effects of fluorinated substitution of meso phenyl porphyrins on porphyrin basicity. The protonation of meso-Tetra(2,3,4-trifluoromethylphenyl) porphyrin (TF) and meso-Tetra(pentafluorophenyl) porphyrin (PF) will be studied through UV vis spectroscopy. Protonation is achieved by titration of each porphyrin in toluene with trifluoroacetic acid (TFA). The presence of a wavelength shift from the free base Soret to the protonated Soret will indicate the formation of a dication. The data from the UV spectra will be used to calculate the pKa values associated with each porphyrin. Based on the results, the average pKa for TF …


Temporal Changes And Possible Sources Of Dissolved Calcium Levels In Stream, River, And Lake Waters In Western Kentucky, Kelsie Meystedt Apr 2022

Temporal Changes And Possible Sources Of Dissolved Calcium Levels In Stream, River, And Lake Waters In Western Kentucky, Kelsie Meystedt

Scholars Week

ABSTRACT

Zebra Mussels (Dreissena polymorpha) are an exotic and invasive mollusk that spread extensively over various rivers and lakes in the United States. These mussels are known for being notorious in their “biofouling” capabilities, costing the U.S. government billions of dollars in removal operations. Recently, zebra mussel colonies were found in Kentucky Lake possibly due to human activities increasing the salinity of today’s freshwater resources. The increase in salinity from human activities may have adversely affected the ecosystems and water supplies. The Specific aim of this study was to determine the temporal trend of dissolved calcium in Kentucky Lake …


Probing Small Heat Shock Protein Chaperoning Activity Through The Interaction Between Myoglobin And Guanidine Hydrochloride, Jacob Mcdowell Apr 2022

Probing Small Heat Shock Protein Chaperoning Activity Through The Interaction Between Myoglobin And Guanidine Hydrochloride, Jacob Mcdowell

Celebration of Research

Myoglobin is a small biological protein found in most muscle tissues. When in the proper form (native/folded), myoglobin can serve its primary function: binding oxygen. However, like all proteins, myoglobin can denature through a variety of processes into a form that no longer binds oxygen. One denaturant, guanidine hydrochloride (GuHCl), is the biological product of protein metabolism. Another class of biological proteins is small heat shock proteins (sHSPs), which have the function of chaperoning other proteins to prevent the denaturing process. Previously, in physical chemistry lab, we explored the GuHCl-induced denaturing of myoglobin. Former Northwestern students used fluorescence correlation spectroscopy …


Amino Acid Quenching, Steven Van Meeteren Apr 2022

Amino Acid Quenching, Steven Van Meeteren

Celebration of Research

Alexa Fluor 594 is a fluorescent molecule commonly used to tag calmodulin, a protein that regulates a variety of cell processes. By measuring fluorescence, scientists can study calmodulin and its interactions with other proteins. However, fluorescence is not the only fate of Alexa Fluor 594. The molecule is also known to transfer energy to coupled amino acids through a mechanism called quenching. The purpose of this experiment was to study the quenching effects of Histidine, Tyrosine, and Methionine on the Alexa Fluor 594. These amino acids’ Stern-Volmer plots suggest static quenching may be occurring. Moreover, the Stern-Volmer plot of Potassium …


Researching The Molecular Components Of Flourish Using Mass Spectroscopy, Lane Mulder Apr 2022

Researching The Molecular Components Of Flourish Using Mass Spectroscopy, Lane Mulder

Celebration of Research

We looked into the molecular composition of a liquid probiotic known as Flourish and and the 13 components that make it up using mass spectroscopy.


Faster Intercalation Pseudocapacitance Enabled By Adjustable Amorphous Titania Where Tunable Isomorphic Architectures Reveal Accelerated Lithium Diffusivity, Wessel Van Den Bergh, Taylor Larison, Maximilliano Jesus Jara Fornerod, Prof. Stefan Guldin, Morgan Stefik Apr 2022

Faster Intercalation Pseudocapacitance Enabled By Adjustable Amorphous Titania Where Tunable Isomorphic Architectures Reveal Accelerated Lithium Diffusivity, Wessel Van Den Bergh, Taylor Larison, Maximilliano Jesus Jara Fornerod, Prof. Stefan Guldin, Morgan Stefik

Faculty Publications

Intercalation pseudocapacitance is a faradaic electrochemical phenomenon with high power and energy densities, combining the attractive features of capacitors and batteries, respectively. Intercalation pseudocapacitive responses exhibit surface-limited kinetics by definition, without restriction from the collective of diffusion-based processes. The surface-limited threshold (SLT) corresponds to the maximum voltage sweep rate (vSLT) exhibiting a predominantly surface-limited current response prior to the onset of diffusion-limitations. Prior studies showed increased lithium diffusivity for amorphous titania compared to anatase. Going beyond prior binary comparisons, here a continuum of amorphous titania configurations were prepared using a series of calcination temperatures to tailor both amorphous …


Competitive Sorption And Transport Of Heavy Metals In Soil And Mn Oxide-Coated Sand, Joshua Tyler Padilla Apr 2022

Competitive Sorption And Transport Of Heavy Metals In Soil And Mn Oxide-Coated Sand, Joshua Tyler Padilla

LSU Doctoral Dissertations

This study investigated the competitive sorption of Ni, Pb, and Zn as well as synergistic interactions between Ni and phosphate (P) in soils and Mn oxide-coated sand. During stirred-flow experiments, the sorption of heavy metal cations by Olivier soil was mutually reduced when applied simultaneously. When applied consecutively, the cation of higher affinity was able to displace the cation of lower affinity from the soil surface, however, no evidence for the reverse case was observed. A novel general exchange kinetics model was able to correctly describe such displacement. Competition between Ni and Zn mutually increased mobility in Olivier and Windsor …


Bioactivity Of Suberitenones A And B, Jared G. Waters Apr 2022

Bioactivity Of Suberitenones A And B, Jared G. Waters

USF Tampa Graduate Theses and Dissertations

Throughout human history, natural products have formed the foundation of medicine. In ancient times, a myriad of herbs and fungi have been attributed properties of healing and rejuvenation. Today, that foundation still very much exists, as natural product chemists isolate bioactive compounds from plants, fungi, animals, and microorganisms alike. As more of these secondary metabolites are discovered, scientists pursue more and more sources of biodiversity that may yield new and unprecedented compounds. To this end, Antarctica has become of particular note, as its unique environmental conditions and highly isolated nature make for rare and unusual adaptations in its native wildlife. …


Ionic Liquids As Both Solvent And Reagent In Electrophilic Addition Reactions, Hannah Artz, Roseann K. Sachs Apr 2022

Ionic Liquids As Both Solvent And Reagent In Electrophilic Addition Reactions, Hannah Artz, Roseann K. Sachs

Honors Projects and Presentations: Undergraduate

Ionic Liquids (ILs) are an environmentally friendly alternative to organic and aqueous reaction solvents. ILs do not emit hazardous gasses, are readily recycled and reused, and often do not require an excess volume of harmful reagents and purification solvents. The IL anion’s capacity to participate in a reaction as the nucleophile source is a much less understood area of this research, and it may advance the use of ILs in organic synthesis, particularly for addition and substitution reactions. Markovnikov hydrohalogenation of alkenes is one addition reaction that is generally taught as an introduction to organic chemical reactions; however, this reaction …